1. Field of the Invention
The present invention relates to storage control technology, and in particular to control of access exclusion.
2. Description of the Related Art
In for example a database system which handles large amounts of data, such as for example a data center, data is managed using a storage system configured separately from host computers. This storage system is for example a disk array system such as a RAID (Redundant Array of Independent Inexpensive Disks) system, configured with numerous storage devices arranged in an array.
One such a storage system is, for example, the magnetic disk subsystem disclosed in Japanese Patent Laid-open No. 5-128002. This subsystem has cache memory 28, a control table 30, and a plurality of magnetic disk devices 24 to 27. The cache memory 28 is divided into a plurality of areas 28A, 28B by tasks processed by host computers 22, 23. The control table 30 is divided into a plurality of control tables 30A, 30B corresponding to the plurality of areas 28A, 28B. The host computers 22, 23 specify, for each area 28A, 28B, the magnetic disk devices 24 to 27.